From 12d217c795071bfee483158e1397c57e8dc3cb76 Mon Sep 17 00:00:00 2001
From: Paulo Zanoni <paulo.r.zanoni@intel.com>
Date: Fri, 3 May 2013 12:15:38 -0300
Subject: [PATCH] drm/i915: clear FPGA_DBG_RM_NOCLAIM when capturing error
 state

In the error state function we read the registers without checking if
the power well is on, so after doing this we have to clear the
FPGA_DBG_RM_NOCLAIM bit to prevent the next I915_WRITE from detecting
it and printing an error message.

The first version of this patch was checking for the power well state
and then avoiding reading registers that were off, but the reviewers
requested to just read the registers any way and then later clear the
FPGA_DBG_RM_NOCLAIM bit.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
---
 drivers/gpu/drm/i915/intel_display.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 260545cc5049..544d766f6ef3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -9842,6 +9842,13 @@ intel_display_capture_error_state(struct drm_device *dev)
 		error->pipe[i].vsync = I915_READ(VSYNC(cpu_transcoder));
 	}
 
+	/* In the code above we read the registers without checking if the power
+	 * well was on, so here we have to clear the FPGA_DBG_RM_NOCLAIM bit to
+	 * prevent the next I915_WRITE from detecting it and printing an error
+	 * message. */
+	if (HAS_POWER_WELL(dev))
+		I915_WRITE_NOTRACE(FPGA_DBG, FPGA_DBG_RM_NOCLAIM);
+
 	return error;
 }
 
-- 
GitLab